A simplified protocol of steroid injection for psoriatic nail dystrophy

Subjects seeking therapy for psoriatic nail dystrophy were recruited from routine clinics and involved digits were scored between 0 and 3 for severity of each of five features: subungual hyperkeratosis, pitting, onycholysis, ridging and thickening. These features were re-scored 2 months after injection of triamcinolone acetonide (0.4 mL, 10 mg/mL) into the nail bed and matrix following ring block, and then at 3-monthly intervals. A second injection was offered at 2 months if warranted by poor response. Forty-six digits were injected in 19 subjects (12 women, 7 men, mean age 48 years) receiving a mean of 1.2 doses. Follow-up ranged from 3 to 17 months (mean 9.4). Results are given for responses sustained up until the last follow-up. Onycholysis was present in 36 digits (78%) and improved in 18 (50%) of these. Pitting was present in 20 (43%), improving in nine (45%) and remaining unchanged in 11 (55%). Subungual hyperkeratosis was present in 16 (35%) and always improved after injection. Ridging was also present in 16 (35%) and improved in all but one instance. Thickening was present in 12 cases (26%), improving in 10 (83%) and remaining unchanged in the rest. Although onycholysis and pitting are the most common elements of psoriatic dystrophy we show that they are the least responsive to steroid injected in this fashion. However, subungual hyperkeratosis, ridging and thickening respond well, with benefit sustained for at least 9 months. When these are the dominant features of a nail dystrophy, treatment according to the protocol in this study appears justified.